Ok, so i have a 92 prelude si as my winter car so i dont have to drive my 2001 turbo tiburon.

Lately i have had a idle problem; I start the car and it stays steady at 1800-2000rpms for about 2 minutes then the idle surges from 1grand to 2grand and will continue to do this anytime im not driving.

I searched and found out that the FIAC or IACV is most likely at fault. So i tore off the throttle body and cant seem to find the FIAC or IACV. Numerous threads say it is under the TB, but the only thing under the TB is a control valve that runs coolant into the TB. i tore it apart anyway and didnt find the white screw i am supposed to tighten so i assumed i was right that this wasnt the FIAC or IACV. I looked around the throttle body opening on the manifold and cant seem to find anything that resembles either the FIAC or IACV.

Heres a pic of the throttle body and a few shots of the IM

 

OK i just saw that the thing on the bottom of the Throttle body IS the FAIC but when i took it off i didnt see any screw that i could tighten. Ill tear it off agian and see

Help is still very much appreciated

 

See what that gray plug goes to right on the front of the intake manifold ? The plug comes from the same loom as the injectors. It goes to the IACV. Just underneath the throttle cable.

3 bolts hold it in place. 12mm if memory serves correctly.

 

ok i cleaned the FAIC (it was pretty dirty where the coolant comes in) but i couldnt find any screw that i could tighten

So I started it and it ran the same as it did before 2000rpm's for 2 minutes or so and then surged 1000-2000rpm's

so i pulled off the IACV and tried to clean it but i cant really figure out what needs cleaning, and i still cant find the little screw you need to tighten, i see where the coolant enters and its got funky screws that i cant get off, is it under that?

here are some pictures







/\ is that it??? thats more of a hex and my friend had the same thing on his mustang and he said it didnt do anything.

 

if you want to fix it cheaply and get it fixed now then grab a business card or somthing that will work as a gasket and put it in between the IACv and the manifold. Just block it off. It worked for me for a yr until i got rid of it. Or you can keep searching for this screw? or just buy a new one.

 

Ok, I started the engine without the intake arm on, it was surging. I put my thumb over the hole on the 8oclock of the throttle body (the one for the FAIC) and the engine stopped surging alltogether, and held a steady idle at 1400rpms. The temperature here is like 40 degrees fahrenheit so it might have something to do with the high idle.

what do you think?



Modified by alex01tib at 8:08 PM 9/11/2006

 

when you adjust your idle ajustment screw can you get your idle down below 1000 rpms. Your Intake manifold is very dirty

 

You need to take off the FITV located directly underneath your throttle body. The small nipple on the top of the FITV has three small phillips head screws(take those out) you will see a large white sleeve looking hollow bolt (it has three notches in the top of it) Stick a flat head screw driver into on of the notches and turn it clockwise to see if it has came loose. If you can turn this with the screw driver you have found your problem tightened it down and put it back together. Hope this helps

Im not sure what part that is located directly under the throttle body is called so excuse me if i gave you the wrong term.

 

https://honda-tech.com/zerothread?id=1564019 Here is a write up .

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 94draglude &raquo;</TD></TR><TR><TD CLASS="quote">if you want to fix it cheaply and get it fixed now then grab a business card or somthing that will work as a gasket and put it in between the IACv and the manifold. Just block it off. It worked for me for a yr until i got rid of it. Or you can keep searching for this screw? or just buy a new one.</TD></TR></TABLE>

By blocking off the IACV all together, did it effect your idle at all?

Has anyone completely blocked off the FITV?

 

Oh ok yah i took that off and i saw the white thing, but somebody said use a screwdriver so i figured i was looking for an actual screw, lol dammit ill take it back off.

SO does what i said in my last post confirm its come loose?

Ill be back in a jiffy

 

That fixed it!

I took it all the way off with my finger on the brake cleaner and noticed it looked brand new, so i just threw it back together and tightened it all the way up; which was way tighter than it was before i took it out.

First impression working on this car wasnt good because of the 2 idle actuators and both of them having coolant running to them, and honda's affinity for phillips head screws that like to strip

. But i did enjoy being able to rev the engine with just the throttle body (without any intake piping or maf sensors hooked up lol.)


Modified by alex01tib at 9:19 PM 9/11/2006

 

hondas use MAP sensors not MAFs

dont tighten that thing down too much, it wont idle fast when its cold...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by bb_one &raquo;</TD></TR><TR><TD CLASS="quote">

By blocking off the IACV all together, did it effect your idle at all?

Has anyone completely blocked off the FITV?</TD></TR></TABLE>
No it didnt effect my idle.

 

"hondas use MAP sensors not MAFs"

DUH! LOL, that was the point of me saying that, because with my tib i have to fully have the IC piping re-attached, even if i just want to test start it.

 

heres the other mod if you dont wanna use a business card
http://92lude.com/idle_air_control_bypass_mod.htm
just did this the other day and no more surging. Nice and smooth. It just snowed here last night and the car idled kinda low for a cold start but no issues.

 

Thats good for other members to see but for my car the surging is all gone and it fast idles great when cold.

 

Hey mine surges when it's cold out, so would I have to adjust the plundger cuz I did it a while back and tightened it all the way down. What seems to be the best number of turns for the fitv plundger?